U S. Pat. No. 4,491,182 discloses a pendent style automatic sprinkler with escutcheon. The escutcheon slips over a smooth, sheet metal housing surrounding the body of the sprinkler.
Pendent style sprinklers are typically installed extending downwardly into or through a ceiling from piping running above the ceiling. The piping supplies water or other fire-retarding fluid to the sprinkler.
Pendant style sprinklers, like that disclosed in U.S. Pat. No. 4,491,182, are often installed in locations where aesthetics are a consideration, such as office buildings, schools, etc. To improve the appearance of such sprinkler installations, covers are preferred which hide the sprinkler and the ceiling opening while the sprinkler is not operating. During a fire, the cover must drop away from the sprinkler, at least by the time the sprinkler activates or "opens", so as not to interfere with the delivery of the water or other fire-retarding fluid through the sprinkler.
One approach which has been widely used for securing a cover to a sprinkler body so that the cover will disconnect from the sprinkler body during the fire, has been to use fusible connectors between the cover and a support member engageable with the sprinkler body. This approach is shown, for example, in U.S. Pat. Nos. 3,393,746, 3,727,695, 4,066,129 and 4,215,751 (FIG. 4). The device disclosed in U.S. Pat. No. 3,393,746 further provides a range of adjustability of the height of the cover on the sprinkler. In each case, the sprinkler and support member are provided with special structures to enable them to engage with one another. The covers cannot be used with sprinklers lacking the special structures to receive the cover support members.
U.S. Pat. No. 3,998,273 discloses a variation on this approach. A fusible connector is used to hold a magnet in place. The cover is coupled to the sprinkler by the magnet. The magnet permits the cover to be mounted to a generally featureless, ferrous housing. However, the height of the cover on the sprinkler is not adjustable and the magnet cannot be used with a non-ferrous housing.
A disadvantage of all of the aforesaid existing systems which use fusible connectors is that the systems must be designed to melt the fusible connector before melting the fusible element which triggers the sprinkler. This delays the response time of the sprinkler.
One advantage of the present invention is that it avoids the use of fusible connectors. This enables the invention to be used with fast responding sprinklers.
Another advantage of the present invention is that it permits the attachment of a cover to a pendent style sprinkler lacking special structures for receiving cover support members.
Other advantages of the invention are that its components are simple, relatively easy to manufacture, relatively easy to retro-fit on the style of pendent sprinkler shown in U.S. Pat. No. 4,491,182, and provide a cover which is adjustable in height with respect to the sprinkler and fully releasable upon opening or activation of the sprinkler.